CN106467164B

CN106467164B - Mitigating surface discontinuities between a flight control surface and a fuselage of an aircraft

Info

Publication number: CN106467164B
Application number: CN201610650167.1A
Authority: CN
Inventors: J·卢瓦耶; D·M·皮特
Original assignee: Boeing Co
Current assignee: Boeing Co
Priority date: 2015-08-20
Filing date: 2016-08-09
Publication date: 2022-01-14
Anticipated expiration: 2036-08-09
Also published as: CA2935181C; EP3135579A1; EP3597530A1; US10000274B2; US20170050720A1; CA2935181A1; EP3135579B1; CN106467164A

Abstract

The present application discloses mitigating surface discontinuities between a flight control surface and a fuselage of an aircraft. A transition element is provided that bridges a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. In one embodiment, the transition element bridges a gap between an edge of the flight control surface and an edge of the immovable portion of the fuselage. The transition element includes a plurality of ribs spanning the gap. Each of the plurality of ribs has a contour that conforms to the flight control surface and is configured to pivot a portion of the rotational angle of the flight control surface to generate a transition surface that spans the gap.

Description

Mitigating surface discontinuities between a flight control surface and a fuselage of an aircraft

Technical Field

The present disclosure relates to the field of aircraft, and in particular to mitigating the effects of gaps between the edges of flight control surfaces of aircraft and the edges of immovable portions of the fuselage.

Background

In order to move the flight control surface of the aircraft relative to the fuselage, a gap exists between the flight control surface and the fuselage. As the flight control surface moves, a discontinuous surface is formed across the gap. During flight, this discontinuous surface generates turbulent airflow across the gap and additional noise, both of which are undesirable. Turbulent airflow increases drag on the aircraft, which reduces fuel economy. The additional noise generated by aircraft is also undesirable because aircraft noise is a common complaint from people living near high-altitude traffic areas (e.g., near airports or under airline travel routes). Accordingly, it is desirable to improve the performance of an aircraft and/or reduce the noise generated by the aircraft by mitigating the discontinuous surfaces generated across the gap between the edge of the flight control surface and the edge of the immovable portion of the fuselage.

Disclosure of Invention

Embodiments provided herein describe transition elements that utilize a plurality of movable ribs spanning a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. The ribs of the transition element have a contour that conforms to the flight control surface and are capable of deflecting or moving as the flight control surface moves. The ribs located closest to the edge of the non-movable portion of the fuselage deflect less, while the ribs located closest to the edge of the flight control surface deflect more. This creates a smooth transition surface across the gap. Embodiments provided herein also describe methods of actuating a transition element.

One embodiment includes a transition element that bridges a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. The transition element includes a plurality of ribs spanning the gap. Each of the plurality of ribs has a contour that conforms to the flight control surface and is configured to pivot a portion of the rotational angle of the flight control surface to generate a transition surface that spans the gap.

Another embodiment is a method for actuating a transition element that bridges a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. The transition element includes a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface. The method includes pivoting a first rib of the plurality of ribs to a first portion of an angle of rotation of the flight control surface, wherein the first rib is positioned closer to an edge of the flight control surface than a second rib of the plurality of ribs. The method further includes pivoting the second rib over a second portion of the rotational angle of the flight control surface, wherein the first portion of the rotational angle is greater than the second portion of the rotational angle. In addition, the plurality of ribs create a transition surface across the gap.

Yet another embodiment is an apparatus comprising a transition element that bridges a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. The transition element includes a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface. The apparatus further includes means for pivoting a first rib of the plurality of ribs to a first portion of a rotational angle of the flight control surface, wherein the first rib is positioned closer to an edge of the flight control surface than a second rib of the plurality of ribs. The apparatus further includes means for pivoting the second rib to a second portion of the angle of rotation of the flight control surface, wherein the first portion of the angle of rotation of the flight control surface is greater than the second portion of the angle of rotation of the flight control surface.

The above summary provides a basic understanding of some aspects of the specification. This summary is not an extensive overview of the specification, and is intended to neither identify key or critical elements of the specification nor delineate any scope of the specific embodiments of the specification or any scope of the claims, but is intended to present some concepts of the specification in a simplified form as a prelude to the more detailed description that is presented later.

Drawings

Some embodiments will now be described, by way of example only, with reference to the accompanying drawings. The same reference numbers will be used throughout the drawings to refer to the same or like elements.

FIG. 1 illustrates, in an exemplary embodiment, an aircraft including a plurality of flight control surfaces.

FIG. 2 illustrates, in an exemplary embodiment, a view of a portion of a wing of the aircraft of FIG. 1.

FIG. 3 illustrates, in an exemplary embodiment, an aileron moving upward at an angle of rotation with respect to the wing of FIG. 2.

FIG. 4 illustrates, in an exemplary embodiment, a transition element for bridging a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage.

Fig. 5 illustrates an enlarged view of the transition element of fig. 4 in an exemplary embodiment.

FIG. 6 illustrates a transition element with some ribs removed in an exemplary embodiment.

FIG. 7 illustrates a side view of a transition element in an exemplary embodiment.

FIG. 8 illustrates a transition element along the leading edge in an exemplary embodiment.

FIG. 9 illustrates another transition element in an exemplary embodiment.

FIG. 10 is a flow chart of a method for actuating a transition element in an example embodiment.

Detailed Description

The figures and the following description illustrate specific exemplary embodiments. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the embodiments and are included within its scope. Moreover, any examples described herein are intended to aid in understanding the principles of the embodiments and are to be construed as being without limitation to such specifically recited examples and conditions. Accordingly, the inventive concept(s) is not limited to the specific embodiments or examples described below, but is defined by the claims and their equivalents.

FIG. 1 illustrates, in an exemplary embodiment, an aircraft 100 that includes a plurality of

flight control surfaces

102 and 107. During flight,

flight control surfaces

102 and 107 allow the pilot to adjust and control the attitude of aircraft 100. The particular configuration of the

flight control surfaces

102 and 107 illustrated with respect to the aircraft 100 varies based on the design of the aircraft 100 and the desired flight characteristics, and thus in other embodiments, the aircraft 100 may include more or fewer

flight control surfaces

102 and 107.

In this embodiment, flight control surfaces 102-107 include both primary and secondary flight control surfaces. As the aircraft 100 flies, the primary flight control surfaces deflect air passing over them. This deflection of air generates unbalanced forces on the aircraft 100 and causes the aircraft 100 to roll, yaw, and pitch during flight. The primary flight control surfaces include ailerons 102, elevators 103, and rudders 104. The ailerons 102 are mounted on the trailing edge of each wing 108 and move in opposite directions. During flight, the pilot uses the ailerons 102 to change the roll of the aircraft 100. The elevators 103 are mounted near the aft portion 110 of the aircraft 100, and during flight, the pilot uses the elevators 103 to change the pitch of the aircraft 100. The rudder 104 is also near the tail 110, and during flight, the pilot uses the rudder 104 to change the yaw of the aircraft 100.

The secondary flight control surfaces include spoilers 105, flaps 106 and slats 107. The spoiler 105 is installed near the trailing edge of the wing 108, and reduces the lift generated by the wing 108 by disturbing the airflow. A pilot of the aircraft 100 may use the spoiler 105 for plunging (dump) lift and allow the aircraft 100 to descend without pitching the aircraft 100 in a nose-down configuration. This may allow the pilot to descend without increasing the speed of the aircraft 100. The flap 106 is mounted on the trailing edge of the wing 108 and/or the leading edge of the wing 108 and is used to increase the effective curvature of the wing 108. The flaps 106 reduce the stall speed of the aircraft 100 and are used during low speed takeoff and landing maneuvers. Slats 107 are mounted on the leading edge of the wing 108 and are used to reduce the stall speed of the aircraft 100 during low speed takeoff and landing maneuvers.

FIG. 2 illustrates, in an exemplary embodiment, a view of a portion of a wing 108 of aircraft 100. In this view, the gap 202 is shown between an edge 206 of the aileron 102 and an edge 208 of the immovable portion of the wing 108. The gap 202 allows the aileron 102 to deflect, move, rotate, etc. with respect to the wing 108 (e.g., with a hinge 204 or other device that rotatably couples the aileron 102 to the wing 108 along its axis of rotation). However, the gap 202 may create problems with respect to airflow over the wing 108. When the aileron 102 is in a neutral position (e.g., neither rotating nor up or down with respect to the major surface of the wing 108), the gap 202 has a relatively small effect on the generation of turbulent airflow around the aileron 102. However, in the deflected or rotated position, a discontinuous surface is formed between the wing 108 and the aileron 102 at both ends of the gap 202.

FIG. 3 illustrates, in an exemplary embodiment, the aileron 102 moving upward at a rotational angle 310 with respect to the wing 108. The aileron 102 includes a leading edge 306, surrounded by the wing 108, and a trailing edge 308. The plurality of arrows illustrate how the profile between the aileron 102 and the wing 108 becomes discontinuous across the gap 202. As air flows over the wing 108 from the leading edge 302 of the wing 108 over the trailing edge 304 of the wing 108, the air flowing through the gap 202 becomes turbulent due to the discontinuous surface formed by the gap 202. Turbulence increases drag on the wing 108 and increases the noise generated by the wing 108. Increased drag will reduce the fuel efficiency of the aircraft 100, and generally any increase in the noise generated by the aircraft 100 is undesirable. A similar discontinuous surface is formed when the aileron 102 is rotated into a downward position with respect to the wing 108. Additionally, while the problems associated with the gap 202 have been and will be discussed with respect to the ailerons 102, similar problems can occur in gaps that exist between the fuselage of the aircraft 100 and the other

flight control surfaces

103 and 107.

FIG. 4 illustrates, in an exemplary embodiment, a transition element 402 that is used to bridge a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage. In this embodiment, the transition element 402 is created by a plurality of thin ribs having a profile similar to the flap 102. If the aileron 102 has a different profile than the wing 108, the ribs may change the profile being fabricated to allow a transition from the profile of the wing 108 to the profile of the aileron 102, which aileron 102 may exist across the gap 202.

In some embodiments, the ribs may be mounted on a member (e.g., a rod, not shown in this view) that spans the gap 202. The edge 208 of the wing 108 does not move, but the edge 206 of the aileron 102 moves. As the flap 102 moves, some of the ribs that make up the transition member 402 move with the flap 102. In particular, the ribs closest to the edge 206 of the aileron 102 move more than the ribs closest to the edge 208 of the wing 108. For example, consider the aileron 102 moving to a position that establishes an angle (e.g., angle 310 of FIG. 3) between the aileron 102 and the wing 108. The first rib closest to the aileron 102 moves relative to the wing 108 by an effective angle that is generally less than the angle established by the aileron 102 relative to the wing 108. The next adjacent rib or second rib movement is generally less than the effective angle of the first rib. Each successive rib located away from the flap 102 moves through a progressively decreasing angle. The angular difference between each successive rib is substantially equal.

As the ribs deflect or move, the ribs form a surface that transitions from the edge 206 of the aileron 102 to the edge 208 of the wing 108 and serve to bridge the gap 202. The transition surfaces are a series of stepped distances between moving or rotating ribs. The step height, smoothness, or effective continuity of the transition surface is determined by the width of the ribs and the angle between each successive rib to create a stepped transition surface. In some embodiments, the angular difference between each rib may vary. In some embodiments, the ribs may have equal widths or unequal widths.

In some embodiments, the ribs are fixed to the member and move in response to a twist or rotation of the member, wherein the twist or rotation of the member varies along the length of the member. In other embodiments, the ribs rotate with or about the member based on the movement of the flaps 102. The ribs fill the gap 202 and form a relatively smooth transition surface from the edge 206 of the aileron 102 to the edge 208 of the wing 108. Transition element 402 reduces drag on wing 108, which improves fuel efficiency of aircraft 100. The transition element 402 may also reduce the acoustic noise generated by the gap 202. In some cases, the transition element 402 may also improve the performance of the flap 102 by reducing the turbulence generated by the gap 202.

Fig. 5 illustrates an enlarged view of the transition element 402 in an exemplary embodiment. In fig. 5, the rib 500 and member 504 are visible. The member 504 may comprise any material capable of twisting or rotating across the gap 202. Some examples of materials that may be used for member 504 include nitinol (which is a metal alloy of nickel and titanium). Other examples include composite materials. The member 504 is disposed across the gap 202 along an axis 512 extending from the wing 108 to the aileron 102.

The rib 502 illustrated in FIG. 5 is near the edge 206 of the flap 102, while the rib 503 is near the edge 208 of the flap 108. In this embodiment, the rib 500 is secured to the member 504. As the flap 102 moves upward (see fig. 4), the amount of twist or rotation of the member 504 varies along the length 506, with the member 504 twisting or rotating at the end 508 closer to the edge 206 of the flap 102 than at the end 510. The increased twist in member 504 causes rib 502 to move upward more than rib 503. The ribs located between the

ribs

502 and 503 will move a proportional amount. For example, the ribs 507 may be shifted approximately half way across the ribs 502 because the ribs 507 are approximately midway between the

ribs

502 and 503.

FIG. 6 illustrates, in an exemplary embodiment, transition element 402 with some ribs 500 removed. In FIG. 6, it is more easily seen that the rib 500 has a leading edge 602 that may coincide with the leading edge 306 of the flap 102 and a trailing edge 604 that may coincide with the trailing edge 308 of the flap 102. It can also be seen from fig. 6 that some of the ribs 500 may be hollow. This may be desirable to reduce the weight of transition member 402. Thus, some of the ribs 500 forming the transition member 402 may be hollow, solid, or a combination of both, as desired. It can also be seen in FIG. 6 that the rib 500 includes an aperture 606 that allows the member 504 to traverse the rib 500. In this embodiment, the rib 500 is bonded or welded to the member 504 along the aperture 606 such that the rib 500 only moves as the member 504 twists. In other embodiments, the rib 500 is not bonded or welded to the member 504.

Fig. 7 illustrates a side view of the transition element 402 in an exemplary embodiment. As the aileron 102 moves upward with respect to the wing at the rotational angle 310, each rib 500 moves or deflects a fraction of the rotational angle 310. In this view, it is apparent that the rib 502 rotates more than the rib 503, wherein the ribs located between the rib 502 and the rib 503 each rotate a portion of the total rotational angle 310. The rib 500 forms a surface 702 that transitions in shape aft from the aileron 102 to the wing 108. The surface 702 is substantially smooth and may have a smoothness that depends on the thickness of the rib 500.

FIG. 8 illustrates, in an exemplary embodiment, transition element 402 along leading edge 604. In this view, a stepped pattern is visible on the surface formed by the rib 500, which stepped pattern depends on the thickness of the rib 500. Although fewer ribs 500 may be used to form transition element 402 (the ribs may be thicker), this will result in a rougher transition surface across gap 202. However, even though thinner ribs form smoother transition surfaces across the gap 202, there are limits to how thin the ribs 500 can be.

Fig. 9 illustrates another transition element 902 in an exemplary embodiment. In this embodiment, the rib 500 is not fixed to the member 504, but is free to pivot or rotate about the member 504. The flexible element 904 is coupled to the trailing edge 604 of the rib 500. The flexible element 904 is also coupled to the trailing edge 308 of the aileron 102 and the trailing edge 304 of the wing 108. As the flap 102 moves upward, the flexible element 904 follows the movement of the trailing edge 308 of the flap 102. This causes the rib 500 to move in the manner already described previously with respect to the transition member 402. In this embodiment, the member 504 may not twist because the twisting of the member 504 is not used to deflect the rib 500. Conversely, the member 504 may be rotatably mounted proximate the edge 208 of the wing 108 and proximate the edge 206 of the aileron 102.

FIG. 10 is a flow chart of a method 1000 of actuating a transition element in an exemplary embodiment. Method 1000 will be discussed with respect to transition element 502 and transition element 902, but method 1000 may also be performed by other transition elements (not shown). The steps of the flow chart for method 1000 may include other steps not shown. Additionally, the steps of the flow chart for method 1000 may be performed in an alternating order.

For this embodiment, the aircraft 100 is considered in flight and the ailerons 102 are in a neutral position. In this case, the neutral position refers to the aileron 102 being aligned with the major surface of the wing 108. For example, the aileron 102 rotates neither upward nor downward with respect to the wing 108. Fig. 2 illustrates this orientation of the flap 102. In the neutral position, the ribs 500 do not deflect or rotate with respect to each other. This is illustrated in fig. 5 and 9. For example, the rib 514 (see fig. 5) (which is immediately adjacent to the rib 516) is flush (e.g., not pivoted) with respect to the rib 514.

To cause a change in the flight orientation of the aircraft 100, the ailerons 102 may be rotated to a commanded position that is different from the neutral position. For example, a pilot of the aircraft 100 may move the ailerons 102 in order to induce rolling of the aircraft 100. In doing so, the aileron 102 is commanded to rotate out of the neutral position. One example of this orientation of the flap 102 is illustrated in FIG. 3. In the deflected or rotated position, the ribs 500 pivot, with ribs closer to the edge of the aileron 102 pivoting more than ribs located closer to the edge 208 of the wing 108.

As the flap 102 rotates, the rib 514 (which is closer to the edge 206 of the flap 102 than the rib 516) pivots a portion of the angle of rotation of the flap 102 (see step 1002). The rib 516 also pivots a portion of the angle of rotation of the flap 102, however, the rib 516 pivots less than the rib 514 because the rib 512 is closer to the edge 206 than the rib 514 (see step 1004). Fig. 8 illustrates how the

ribs

512 and 514 pivot differently. If the angle of rotation 310 is the total rotation of the flap 102, then it can be seen from FIG. 8 that the rib 514 pivots more than the rib 514 because the deflection 804 of the rib 514 is greater than the deflection 802 of the rib 516. This occurs because the rib 514 is closer to the edge 206 of the flap 102 than the rib 516. Each successive rib between rib 516 and edge 208 of wing 108 deflects or pivots less. This results in a rotation angle 310 of each successive rib for a smaller portion of the aileron 102 towards the edge 208 of the wing 108.

Although the previous discussion of transition element 402 and transition element 902 has been described with respect to a particular flight control surface (i.e., aileron 102), transition element 402 and/or transition element 902 may be used with any flight control surface that moves relative to a fixed portion of the fuselage of an aircraft. Some example surfaces include

flight control surface

103 and 107 illustrated in FIG. 1, although other surfaces have not been previously shown or described, other surfaces may also be enhanced with transition elements 402 and/or transition elements 902 to mitigate the discontinuous surfaces generated as the surfaces move.

Utilizing transition element 402 and/or transition element 902 to bridge the gap created between

flight control surface

102 and 107 and the immovable portion of the fuselage of aircraft 100, the discontinuous surface created by the gap is reduced or eliminated, resulting in a smoother transition surface across the gap. This reduces the turbulence generated by the gap, providing the benefits previously described.

In the following clauses, various embodiments are further described:

clause 1. an apparatus, comprising a transition element configured to bridge a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage, the transition element including a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface and is configured to pivot a portion of an angle of rotation of the flight control surface to generate the transition surface spanning the gap.

The apparatus of clause 2. the apparatus of clause 1, wherein the transition element further comprises a member spanning the gap and having a first end coupled to the flight control surface proximate the edge and a second end coupled to the fuselage proximate the edge of the immovable portion; and wherein each of the plurality of ribs is coupled to the member along a length of the member.

Clause 3. the device of clause 2, wherein the first end of the member is rigidly coupled to the flight control surface proximate the edge; the second end of the member is rigidly coupled proximate to an edge of the immovable portion of the fuselage; the twist of the member varies along the length of the member in response to the angle of rotation of the flight control surface; and each of the plurality of ribs is configured to pivot a portion of the rotational angle of the flight control surface in response to the twisting of the member to generate a transition surface that spans the gap.

Clause 4. the apparatus of any one of clauses 2 and 3, wherein at least one of the first end of the member and the second end of the member is rotatably coupled to the vicinity of the edge; and a plurality of ribs rotatably mounted to the member along the length of the member; and the transition element further comprises a flexible element coupled to the trailing edge portion of the plurality of ribs, the flexible element configured to be coupled to the trailing edge portion of the flight control surface and the trailing edge portion of the non-movable portion of the fuselage; wherein the flexible element is configured to move in response to a rotation angle of the flight control surface; and wherein each of the plurality of ribs is configured to pivot a portion of the angle of rotation of the flight control surface in response to movement of the flexible element to generate a transition surface that spans the gap.

Clause 5. the device of any one of clauses 2-4, wherein the member defines an axis extending from an edge of the flight control surface to an edge of the immovable portion of the fuselage; and the plurality of ribs pivot about the axis of the member.

Clause 6. the apparatus of any of clauses 2-5, wherein the member is coupled to the flight control surface near an edge along the rotational axis of the flight control surface.

Clause 7. the device of any one of clauses 1-6, wherein the plurality of ribs comprises a first rib and a second rib adjacent the first rib, the first rib positioned closer to an edge of the flight control surface than the second rib; the first rib pivots a first portion of the angle of rotation of the flight control surface; the second rib pivots a second portion of the angle of rotation of the flight control surface; and the first portion is larger than the second portion.

Clause 8. the device of any one of clauses 1-7, wherein the plurality of ribs establish a stepped transition surface across the gap.

Clause 9. the apparatus of any of clauses 1-8, wherein the angle of rotation of the flight control surface is generated based on movement of the flight control surface from the first position to the second position; the first position is a neutral position; and the second position is a commanded position that is different from the first position.

Clause 10. the device of any one of clauses 1-9, wherein at least one of the plurality of ribs is hollow.

Clause 11. the device of any one of clauses 1-10, wherein the plurality of ribs includes a leading edge aligned with the leading edge of the flight control surface.

Clause 12. the device of any one of clauses 1-11, wherein the plurality of ribs includes a trailing edge aligned with the trailing edge of the flight control surface.

Clause 13. the apparatus of any of clauses 1-12, wherein the flight control surface comprises at least one of an aileron, an elevator, and a rudder.

Clause 14. a method of bridging a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage using a transition element, the transition element comprising a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface, the method comprising pivoting a first rib of the plurality of ribs to a first portion of a rotational angle of the flight control surface, wherein the first rib is positioned closer to the edge of the flight control surface than a second rib of the plurality of ribs; and a second portion of the angle of rotation that pivots the second rib to the flight control surface; wherein the first portion of the angle of rotation is greater than the second portion of the angle of rotation; wherein the plurality of ribs create a transition surface across the gap.

Clause 15. the method of clause 14, further comprising pivoting a third rib of the plurality of ribs to a third portion of the rotational angle of the flight control surface, wherein the third rib is positioned farther from the edge of the flight control surface than the second rib, wherein the second portion of the rotational angle is greater than the third portion of the rotational angle.

Clause 16. the method of any of clauses 14 and 15, further comprising creating a stepped transition surface across the gap, wherein the stepped transition surface comprises a plurality of ribs.

Clause 17. the method of any of clauses 14-16, wherein the flight control surface comprises at least one of an aileron, an elevator, and a rudder.

Clause 18. an apparatus comprising a transition element bridging a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage, the transition element including a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface; means for pivoting a first rib of the plurality of ribs to a first portion of an angle of rotation of the flight control surface, wherein the first rib is positioned closer to an edge of the flight control surface than a second rib of the plurality of ribs; and means for pivoting the second rib to a second portion of the angle of rotation of the flight control surface, wherein the first portion of the angle of rotation is greater than the second portion of the angle of rotation.

Clause 19. the apparatus of clause 18, further comprising means for pivoting a third rib of the plurality of ribs to a third portion of the rotational angle of the flight control surface, wherein the third rib is positioned farther from the edge of the flight control surface than the second rib, wherein the second portion of the rotational angle is greater than the third portion of the rotational angle.

Clause 20. the apparatus of any one of clauses 18 and 19, wherein the flight control surface comprises at least one of an aileron, an elevator, and a rudder.

Although specific embodiments have been described herein, the scope is not limited to those specific embodiments. Rather, the scope is defined by the appended claims and any equivalents thereof.

Claims

1. An aircraft, comprising:

a flight control surface;

an immovable part of a fuselage of the aircraft;

a transition element configured to bridge a gap between an edge of the flight control surface and an edge of the immovable portion of the fuselage, the transition element comprising:

a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface and is configured to pivot a portion of an angle of rotation of the flight control surface to generate a transition surface spanning the gap;

wherein the transition element further comprises:

a member spanning the gap and having a first end coupled to the flight control surface proximate the edge and a second end coupled to the fuselage proximate the edge of the immovable portion; and is

Wherein each of the plurality of ribs is coupled to the member along a length of the member; and is

Wherein the first end of the member is rigidly coupled proximate to the edge of the flight control surface;

the second end of the member is rigidly coupled proximate to the edge of the immovable portion of the fuselage;

a twist of the member varies along a length of the member in response to the angle of rotation of the flight control surface; and

each of the plurality of ribs is configured to pivot the portion of the rotational angle of the flight control surface to generate the transition surface that spans the gap in response to the twisting of the member.

2. The aircraft of claim 1, wherein:

the plurality of ribs being rotatably mounted to the member along a length of the member; and is

The transition element further comprises:

a flexible element coupled to trailing edge portions of the plurality of ribs, the flexible element configured to be coupled to a trailing edge portion of the flight control surface and a trailing edge portion of the immovable portion of the fuselage;

wherein the flexible element is configured to move in response to the angle of rotation of the flight control surface; and is

Wherein each of the plurality of ribs is configured to pivot a portion of the rotational angle of the flight control surface in response to movement of the flexible element to generate the transition surface that spans the gap.

3. The aircraft of claim 1, wherein:

the member defining an axis extending from the edge of the flight control surface to the edge of the immovable portion of the fuselage; and is

The plurality of ribs pivot about the axis of the member.

4. The aircraft of claim 1, wherein:

the member is coupled to the flight control surface near the edge along an axis of rotation of the flight control surface.

5. The aircraft of claim 1, wherein:

the plurality of ribs includes a first rib and a second rib adjacent the first rib, the first rib being positioned closer to the edge of the flight control surface than the second rib;

the first rib pivots a first portion of the angle of rotation of the flight control surface;

the second rib pivots a second portion of the angle of rotation of the flight control surface; and is

The first portion is larger than the second portion.

6. The aircraft of claim 1, wherein:

generating the angle of rotation of the flight control surface based on movement of the flight control surface from a first position to a second position;

the first position is a neutral position; and is

The second position is a commanded position that is different from the first position.

7. The aircraft of any one of claims 1-6, wherein there is at least one of:

at least one of the plurality of ribs is hollow; the plurality of ribs establishing a stepped transition surface across the gap; the plurality of ribs includes a leading edge aligned with a leading edge of the flight control surface; the plurality of ribs includes a trailing edge aligned with a trailing edge of the flight control surface; or the flight control surface comprises at least one of an aileron, an elevator, and a rudder.

8. A method of bridging a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage using a transition element that includes a plurality of ribs that span the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface, the method comprising:

pivoting a first rib of the plurality of ribs for a first portion of an angle of rotation of the flight control surface, wherein the first rib is positioned closer to the edge of the flight control surface than a second rib of the plurality of ribs; and

pivoting the second rib a second portion of the rotational angle of the flight control surface;

wherein the first portion of the rotational angle is greater than the second portion of the rotational angle;

wherein the plurality of ribs create a transition surface across the gap;

wherein the transition element further comprises:

9. The method of claim 8, further comprising:

pivoting a third rib of the plurality of ribs for a third portion of the angle of rotation of the flight control surface, wherein the third rib is positioned farther from the edge of the flight control surface than the second rib, wherein the second portion of the angle of rotation is greater than the third portion of the angle of rotation.

10. The method of any one of claims 8 and 9, further comprising at least one of:

establishing a stepped transition surface across the gap, wherein the stepped transition surface includes the plurality of ribs; the flight control surface includes at least one of an aileron, an elevator, and a rudder.

11. An apparatus for bridging a gap between an edge of a flight control surface and an edge of an immovable portion of a fuselage using a transition element, the apparatus comprising:

the transition element comprising a plurality of ribs spanning the gap, wherein each of the plurality of ribs has a contour that conforms to the flight control surface;

means for pivoting a first rib of the plurality of ribs for a first portion of an angle of rotation of the flight control surface, wherein the first rib is positioned closer to the edge of the flight control surface than a second rib of the plurality of ribs; and

means for pivoting the second rib a second portion of the rotational angle of the flight control surface, wherein the first portion of the rotational angle is greater than the second portion of the rotational angle;

wherein the transition element further comprises:

12. The apparatus of claim 11, further comprising:

means for pivoting a third rib of the plurality of ribs for a third portion of the angle of rotation of the flight control surface, wherein the third rib is positioned farther from the edge of the flight control surface than the second rib, wherein the second portion of the angle of rotation is greater than the third portion of the angle of rotation.

13. The apparatus according to any one of claims 11 and 12, wherein:

the flight control surface includes at least one of an aileron, an elevator, and a rudder.